Polyimide vibration film and its production process

Abstract

The present invention discloses a polyimide vibrating film and a production process thereof, relating to the technical field of polyimides. By introducing 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl monomer as a fifth monomer into 4,4'-diaminodiphenyl ether, 3,3,4,4-diphenyl ether tetracarboxylic dianhydride, 3,3,4,4,-biphenyl dianhydride, and pyromellitic dianhydride monomers, the prepared polyimide film exhibits excellent mechanical properties, a low dielectric constant, a high elongation at break, and stable voltage breakdown resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polyimide, and in particular to a polyimide vibration film and a production process thereof. Background Art

[0002] Polyimides are a class of polymers containing imide rings in their backbones. They possess excellent electrical and mechanical properties, as well as solvent and high-temperature resistance. Consequently, they are widely used in aerospace, the electronic information industry, and microelectronics. In microelectronics, polyimide film, a dielectric material with excellent flexibility, can, through modification, exhibit low dielectric constants, high-temperature resistance, high elasticity, and self-lubrication. This makes it a highly sought-after material for ultra-thin and lightweight diaphragms in high-end audio systems.

[0003] The performance requirements for polyimide film used in isolation tapes for automated TAB carrier tape soldering are essentially the same as those for high-frequency vibration polyimide film used in audio equipment and other applications. Currently, the predominant carrier used on the market is a double-layer carrier tape consisting of polyimide film laminated onto aluminum foil. This material, called Al-TAB, is a very thin, double-layer material, approximately 50μm thick (30μm aluminum layer, 20μm polyimide layer) and 100mm wide. This material requires the polyimide film to possess high elasticity and flexibility, as well as a low dielectric constant. The aluminum layer acts as a conductor, while the polyimide layer provides support and protection.

[0004] Traditional polyimide films are limited in their application requirements for high plasticity and high elasticity. The main reason is that the tensile strength of polyimide is too high and the elongation at break is too low. It is impossible to meet the high plasticity requirement while ensuring the tensile strength while also ensuring that the breakdown voltage requirement is met. In order to increase the elongation of ordinary polyimide films, the tensile strength of the film is reduced, so that the support of the film does not meet the corresponding requirements; and in order to improve the breakdown resistance, the Young's modulus needs to be increased, which in turn makes the film overall harder; currently, the main method on the market is to introduce a support body into the polyimide material through foaming technology or filling with inorganic particles, thereby reducing the number of polarized molecules per unit volume of the polyimide material and thus reducing its dielectric constant. The existing technology uses spherical silicon and polyimide film to composite, and then removes the spherical silicon by hydrofluoric acid etching. The dielectric constant of the porous polyimide film produced is as low as 1.6. However, the mechanical properties of the film obtained by this method are seriously deteriorated and it is only applicable in special fields.

[0005] In summary, how to make the polyimide film meet the requirements of high plasticity while ensuring tensile strength and at the same time ensuring breakdown resistance is an urgent problem to be solved. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology, provide a polyimide vibration film and its production process, and introduce TFMB monomer to participate in copolymerization, so that the prepared polyimide film has excellent mechanical properties, low dielectric constant, high elongation at break and stable voltage breakdown resistance.

[0007] The technical solution of the present invention is:

[0008] In one aspect, the present invention provides a production process for a polyimide vibrating film, comprising the following steps:

[0009] S1: 4,4'-diaminodiphenyl ether (ODA), 3,3,4,4-diphenyl ether tetracarboxylic dianhydride (ODPA), 3,3,4,4,-biphenyl dianhydride (BPDA) and pyromellitic dianhydride (PMDA) are added as base materials into an organic solvent, stirred and dissolved, and the solid content is adjusted to 18-20 wt.%, stirred and reacted at room temperature for 8-10 hours to obtain a prepolymer solution;

[0010] S2: Add 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl (TFMB) to an organic solvent and stir to dissolve it to obtain a 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution, which is then injected into the prepolymer solution to obtain a fluorinated polyamic acid solution (FPAA) with a solid content of 20-22 wt.%, which is then degassed and filtered and temporarily stored in a storage tank;

[0011] S3: Add acetic anhydride and isoquinoline to an organic solvent, mix them, defoam, and filter them into their respective storage tanks for temporary storage. Acetic anhydride is a dehydrating agent, and isoquinoline is a catalyst. When FPAA is imidized at low temperature, the addition of isoquinoline can accelerate the imidization. During the acceleration of the imidization, the dehydration reaction will also accelerate, and water molecules need the assistance of acetic anhydride to be removed.

[0012] S4: The three materials in the storage tanks of step S2 and step S3 are transported to the pin-bar mixer above the die head, and after being fully mixed at -15~-5℃, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in the casting machine to complete the preliminary imidization film shaping, and then the imidization is completed after shaping in a stretching machine, and finally rolled up to obtain a polyimide vibration film.

[0013] When acetic anhydride, isoquinoline, and FPAA are mixed in a pin-bar mixer, high-speed friction generates heat, which accelerates the catalytic rate of isoquinoline and the dehydration rate of acetic anhydride in the pin-bar mixer. In order to prevent the catalytic and dehydration reactions of imidization in the pin-bar mixer and the die head, acetic anhydride, isoquinoline, and FPAA are mixed at a low temperature of -15 to -5°C to prevent the reaction from occurring.

[0014] When preparing polyimide film by the chemical method, the upper layer is dehydrated and imidized using 135°C hot air in a casting machine, while the lower layer is desolvated using 145°C hot air. The dehydrating agent, acetic anhydride, accelerates the removal of water molecules during the imidization process. Because at 135°C, the upper layer's solvent has not yet been removed, the solids content remains unchanged, and the film's surface is neither solidified nor sealed, allowing water molecules to escape easily. This results in a rapid evaporation rate for water molecules and a high degree of imidization completion, allowing the majority of the imidization to be completed in the casting machine. After the film exits the casting machine, it enters a stretching machine, where the high temperature evaporates and removes any remaining solvent. This simultaneously completes the remaining imidization reaction, removes isomers within the film, and stabilizes its dimensions, ultimately resulting in a fully imidized polyimide film.

[0015] Preferably, the specific process of step S1 is as follows: 4,4'-diaminodiphenyl ether (ODA), 3,3,4,4-diphenyl ether tetracarboxylic dianhydride (ODPA), 3,3,4,4,-biphenyl dianhydride (BPDA) and pyromellitic dianhydride (PMDA) are dissolved in an organic solvent in a separate monomer tank, and nitrogen is introduced for protection; the obtained 3,3,4,4,-biphenyl dianhydride (BPDA) solution is put into the first reactor, and after uniform stirring, the 4,4'-diaminodiphenyl ether (ODA) solution and the 3,3,4,4-diphenyl ether tetracarboxylic dianhydride (ODPA) solution are gradually added, and after stirring, the pyromellitic dianhydride (PMDA) solution is gradually added, and uniform stirring is performed for 8-10 hours until the designed viscosity is reached to obtain a uniformly mixed prepolymer solution, and nitrogen is introduced for protection; after degassing, the solution is filter-filtered and temporarily stored in a storage tank.

[0016] Preferably, in the base material, the molar ratio of 4,4'-diaminodiphenyl ether (ODA), 3,3,4,4,-biphenyl dianhydride (BPDA), 3,3,4,4-diphenyl ether tetracarboxylic dianhydride (ODPA) and pyromellitic dianhydride (PMDA) is 1:(0.3-0.39):(0.3-0.39):(0.3-0.34), and the molar ratio of anhydride to amino group is 0.99:1.

[0017] Preferably, the designed viscosity is 450,000-500,000 mPa·s at 25°C.

[0018] Preferably, the specific process of step S2 is as follows: adding 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl (TFMB) to an organic solvent and stirring to dissolve it to obtain a 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution, and passing nitrogen for protection; injecting the 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution into the prepolymer solution, adjusting it to the designed viscosity, obtaining a fluorinated polyamic acid solution (FPAA), and passing nitrogen for protection.

[0019] Preferably, in step S2, the molar ratio of the solid in the fluorine-containing polyamic acid solution to 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl is 1:(0.02-0.04).

[0020] Preferably, the designed viscosity is 1 million to 1.2 million mPa·s at 25°C.

[0021] Preferably, in step S3, the mass of acetic anhydride is 30-35 times the mass of the base material, the mass ratio of acetic anhydride to the organic solvent is (0.8-1): (2.2-2.8), the mass of isoquinoline is 5.5-6.5 times the mass of the base material, and the mass ratio of isoquinoline to the organic solvent is (0.8-1): (3-5).

[0022] Preferably, the drying temperature of the upper layer of the casting machine is 135°C, and the drying temperature of the lower layer is 145°C. The setting temperature of the stretching machine is: 180-220°C in the first hot air section, 200-240°C in the second hot air section, 240-260°C in the third infrared section, and 220-270°C in the fourth infrared section. The present invention utilizes the rigid monomers (ODPA and BPDA) in the quaternary monomers and their added amounts to achieve excellent performance of the polyimide vibrating film at a relatively low setting temperature.

[0023] On the other hand, the present invention provides a polyimide vibration film produced by the above-mentioned production process of the polyimide vibration film.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] In the production of polyimide vibrating film, the present invention introduces TFMB monomers into the copolymerization process. While the main polymer chain remains primarily polyimide, the polymer's glass transition temperature and high-temperature weight loss remain unchanged. The introduction of TFMB as a fifth monomer disrupts the regularity of the polyimide main chain, lowering the polymer's crystallization temperature and making the film easier to process. This type of fluorinated monomer has a cyclic structure and inherently large free volume. Furthermore, the fluorine structure segregates from the polyimide main chain. Therefore, the fluorobenzene structure of the TFMB side chain forms a spatial entanglement in the side chains of the fluorinated polyamic acid liquid polymer chain segments, further increasing the free volume and enabling the resulting fluorinated polyimide film to have a dielectric constant as low as 1.74. At the same time, after imidization, the molecular chains of the polyimide film have a tight structure and excellent mechanical properties, which not only makes it have a low dielectric constant, but also has the characteristics of high temperature resistance, high elasticity, and self-lubrication. It can always maintain a high elongation at break at a high temperature of 200°C, and has stable voltage breakdown resistance and a low dielectric constant under automatic welding conditions after being combined with aluminum sheets. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 13 is the DSC curve of the polyimide vibrating film prepared in Example 1 of the present invention.

[0027] Figure 2 This is the thermal decomposition curve of the polyimide vibration film prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0029] Example 1

[0030] The production process of the polyimide vibrating film of this embodiment includes the following steps:

[0031] S1: Take ODA, BPDA, ODPA, and PMDA and dissolve them with DMF in separate monomer tanks, and pass nitrogen for protection; put the obtained BPDA solution into the first reactor, stir at a uniform speed, and then gradually add ODA solution and ODPA solution. The molar ratio of ODA, BPDA, and ODPA is 1:0.39:0.3. After stirring, gradually add PMDA solution. The molar ratio of PMDA to ODA is 0.3:1. The molar ratio of anhydride and amine groups is controlled to be 0.99:1, and the solid content is adjusted to 18wt.%. Stir and react at room temperature for 9h to obtain a prepolymer solution with a viscosity of 500,000 mPa·s (25℃), and pass nitrogen for protection; after degassing, filter and temporarily store in a storage tank;

[0032] S2: TFMB was added to DMF and stirred to dissolve to obtain a TFMB solution, which was then protected by nitrogen. The solution was injected into the prepolymer solution to obtain a fluorinated polyamic acid solution (FPAA) with a solid content of 20 wt.% and a viscosity of 1 million mPa·s (at 25°C). The molar ratio of the solid in FPAA to TFMB was 1:0.04, and nitrogen was passed through the solution. The solution was transferred to a defoaming kettle for degassing, and after completion, it was filter-filtered and temporarily stored in a storage tank.

[0033] S3: Add acetic anhydride and isoquinoline to DMF respectively and mix well. The amount of acetic anhydride is 30 times the mass of the base material, and the mass ratio of acetic anhydride to DMF is 1:2.8. The amount of isoquinoline is 5.5 times the mass of the base material, and the mass ratio of isoquinoline to DMF is 1:5. After defoaming, filter press and temporarily store in respective storage tanks;

[0034] S4: The three materials in the storage tanks of step S2 and step S3 are transported to the needle-bar mixer above the die head through a metering pump. After being fully mixed at -5°C, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in two layers at 135°C and 145°C in the casting machine to complete the preliminary imidization film setting. After that, the belt is set in the first zone hot air section of the stretching machine at 220°C, the second zone hot air section at 230°C, the third zone infrared section at 260°C, and the fourth zone infrared section at 270°C, the imidization is completed, and the polyimide vibration film is finally wound up.

[0035] Example 2

[0036] The production process of the polyimide vibrating film of this embodiment includes the following steps:

[0037] S1: Dissolve ODA, BPDA, ODPA, and PMDA with DMF in separate monomer tanks, and introduce nitrogen for protection; add the obtained BPDA solution into the first reactor, stir at a uniform speed, and gradually add the ODA solution and ODPA solution. The molar ratio of ODA, BPDA, and ODPA is 1:0.35:0.34. After stirring, gradually add the PMDA solution. The molar ratio of PMDA to ODA is 0.3:1. The molar ratio of anhydride to amine is controlled to be 0.99:1, and the solid content is adjusted to 18 wt.%. Stir and react at room temperature for 8 h to obtain a prepolymer solution with a viscosity of 480,000 mPa·s (25°C), which is then introduced with nitrogen for protection; after degassing, filter press and temporarily store in a storage tank;

[0038] S2: TFMB was added to DMF and stirred to dissolve to obtain a TFMB solution, which was then protected by nitrogen. The solution was injected into the prepolymer solution to obtain a fluorinated polyamic acid solution (FPAA) with a solid content of 20 wt.% and a viscosity of 1.1 million mPa·s (at 25°C). The molar ratio of the solid in FPAA to TFMB was 1:0.03, and nitrogen was passed through the solution. The solution was transferred to a defoaming kettle for degassing, and after completion, it was filter-filtered and temporarily stored in a storage tank.

[0039] S3: Add acetic anhydride and isoquinoline to DMF respectively and mix well. The amount of acetic anhydride is 35 times the mass of the base material, and the mass ratio of acetic anhydride to DMF is 0.9:2.5. The amount of isoquinoline is 6 times the mass of the base material, and the mass ratio of isoquinoline to DMF is 0.9:4. After defoaming, filter press and temporarily store in respective storage tanks;

[0040] S4: The three materials in the storage tanks of step S2 and step S3 are transported to the needle-bar mixer above the die head through a metering pump. After being fully mixed at -10°C, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in two layers at 135°C and 145°C in the casting machine to complete the preliminary imidization film shaping. After that, the belt is shaped in the first zone hot air section of the stretching machine at 200°C, the second zone hot air section at 240°C, the third zone infrared section at 240°C, and the fourth zone infrared section at 260°C to complete the imidization. Finally, the belt is rolled up to obtain the polyimide vibration film.

[0041] Example 3

[0042] The production process of the polyimide vibrating film of this embodiment includes the following steps:

[0043] S1: Dissolve ODA, BPDA, ODPA, and PMDA with DMF in separate monomer tanks, and introduce nitrogen for protection; add the obtained BPDA solution into the first reactor, stir at a uniform speed, and gradually add the ODA solution and ODPA solution. The molar ratio of ODA, BPDA, and ODPA is 1:0.3:0.39. After stirring, gradually add the PMDA solution. The molar ratio of PMDA to ODA is 0.3:1. The molar ratio of anhydride to amine is controlled to be 0.99:1, and the solid content is adjusted to 20 wt.%. Stir and react at room temperature for 10 h to obtain a prepolymer solution with a viscosity of 450,000 mPa·s (25°C), and introduce nitrogen for protection; after degassing, filter and temporarily store in a storage tank;

[0044] S2: TFMB was added to DMF and stirred to dissolve to obtain a TFMB solution, which was then protected by nitrogen. The solution was injected into the prepolymer solution to obtain a fluorinated polyamic acid solution (FPAA) with a solid content of 22 wt.% and a viscosity of 1.2 million mPa·s (at 25°C). The molar ratio of the solid in FPAA to TFMB was 1:0.02, and nitrogen was passed through the solution. The solution was transferred to a defoaming kettle for degassing, and after completion, it was filter-filtered and temporarily stored in a storage tank.

[0045] S3: Add acetic anhydride and isoquinoline to DMF respectively and mix well. The amount of acetic anhydride is 32 times the mass of the base material, and the mass ratio of acetic anhydride to DMF is 0.8:2.2. The amount of isoquinoline is 6.5 times the mass of the base material, and the mass ratio of isoquinoline to DMF is 0.8:3. After defoaming, filter press and temporarily store in respective storage tanks;

[0046] S4: The three materials in the storage tanks of step S2 and step S3 are transported to the needle-bar mixer above the die head through a metering pump. After being fully mixed at -15°C, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in two layers at 135°C and 145°C in the casting machine to complete the preliminary imidization film shaping. After that, the belt is shaped in the first zone hot air section of the stretching machine at 180°C, the second zone hot air section at 200°C, the third zone infrared section at 250°C, and the fourth zone infrared section at 260°C to complete the imidization. Finally, the belt is rolled up to obtain the polyimide vibration film.

[0047] Example 4

[0048] The production process of the polyimide vibrating film of this embodiment includes the following steps:

[0049] S1: Dissolve ODA, BPDA, ODPA, and PMDA with DMF in separate monomer tanks, and introduce nitrogen for protection; add the obtained BPDA solution into the first reactor, stir at a uniform speed, and gradually add the ODA solution and ODPA solution. The molar ratio of ODA, BPDA, and ODPA is 1:0.35:0.3. After stirring, gradually add the PMDA solution. The molar ratio of PMDA to ODA is 0.34:1. The molar ratio of anhydride to amine is controlled to be 0.99:1, and the solid content is adjusted to 20 wt.%. Stir and react at room temperature for 8 h to obtain a prepolymer solution with a viscosity of 480,000 mPa·s (25°C), which is then introduced with nitrogen for protection; after degassing, filter press and temporarily store in a storage tank;

[0050] S2: TFMB was added to DMF and stirred to dissolve to obtain a TFMB solution, which was then protected by nitrogen. The solution was injected into the prepolymer solution to obtain a fluorinated polyamic acid solution (FPAA) with a solid content of 20 wt.% and a viscosity of 1.1 million mPa·s (at 25°C). The molar ratio of the solid in FPAA to TFMB was 1:0.02, and nitrogen was passed through the solution. The solution was transferred to a defoaming kettle for degassing, and after completion, it was filter-filtered and temporarily stored in a storage tank.

[0051] S3: Add acetic anhydride and isoquinoline to DMF respectively and mix well. The amount of acetic anhydride is 30 times the mass of the base material, the amount of DMF is 2.8 times the mass of acetic anhydride, the amount of isoquinoline is 5.5 times the mass of the base material, and the amount of DMF is 5 times the mass of isoquinoline. After defoaming, filter press and temporarily store in respective storage tanks.

[0052] S4: The three materials in the storage tanks of step S2 and step S3 are transported to the needle-bar mixer above the die head through a metering pump. After being fully mixed at -5°C, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in two layers at 135°C and 145°C in the casting machine to complete the preliminary imidization film setting. After that, the belt is set in the first zone hot air section of the stretching machine at 220°C, the second zone hot air section at 240°C, the third zone infrared section at 260°C, and the fourth zone infrared section at 220°C to complete the imidization. Finally, the belt is rolled up to obtain the polyimide vibration film.

[0053] Comparative Example 1

[0054] The difference from Example 1 is that step S2 is not performed, and the material of step S2 transported to the pin-bar mixer above the die head in step S4 is replaced by the prepolymer liquid of step S1.

[0055] Comparative Example 2

[0056] Comparative Example 2: A polyimide film was prepared by sintering spherical silicon doping, specifically comprising the following steps:

[0057] (1) Take sintered spherical silicon (SiO2 type raw material provided by EIT Co., Ltd., Japan), ultrasonically disperse it with 5 times the mass of DMF, add 3% of the mass of the dispersion liquid silane coupling agent KH550, and stir at room temperature for 1 hour to obtain coupled spherical silicon;

[0058] (2) According to step S1 of Example 4, a prepolymer solution is obtained;

[0059] (3) According to step S2 of Example 4, coupled spherical silica was used instead of TMFB, and coupled spherical silica was added to the prepolymer solution at a mass ratio of 6.5% of the base material;

[0060] (4) Same as steps S3 and S4 of Example 4.

[0061] Samples were taken from the polyimide vibration films prepared in Examples 1-4 and Comparative Examples 1-2 to perform performance tests. The test method is as follows:

[0062] 1) DSC test was performed on the sample using a DSC-Q100 instrument: in a nitrogen atmosphere with a flow rate of 50 mL / min, the sample was heated from 60°C to 270°C at a heating rate of 10°C / min, held for 1 minute, and then cooled to 60°C at a cooling rate of 10°C / min. The above heating and cooling operations were repeated, and the values of the second heating and cooling curves were taken as experimental data to measure the glass transition temperature T of the polyimide vibrating film of Example 1. g like Figure 1 As shown by Figure 1 It can be seen that the glass transition temperature T g=277℃.

[0063] 2) The tensile properties of the samples were tested using a SHIMADZU AG-I universal testing machine at room temperature and a tensile rate of 5 mm / min.

[0064] 4) The dielectric constant of the sample was tested using a JKY / 1920 / M315427 LCR instrument at a temperature of 25°C and a frequency of 1-1000 kHz.

[0065] The performance test results of the polyimide vibration films prepared in Examples 1-4 and Comparative Examples 1-2 are shown in Table 1:

[0066] Table 1 Performance test results of polyimide vibration films prepared in Examples 1-4 and Comparative Examples 1-2

[0067]

[0068] As shown in Table 1, compared with Comparative Example 1, the dielectric constant of the thin film materials prepared in Examples 1-4 decreased significantly with the addition of monomer TFMB, and the dielectric constant at 1 MHz was only 1.74-1.99, which has a lower dielectric constant, making it easier to process in practical applications.

[0069] As can be seen from Table 1, in Comparative Example 2, which does not contain TFMB, sintered spherical silicon is added to reduce the dielectric constant of the membrane surface. However, the addition of inorganic fillers will result in poor length of the functional bond chain, and the tensile strength and elongation at break of the membrane are not as good as those of TFMB, a monomer that can undergo a bonding reaction.

[0070] The present invention obtains a polymer material with excellent tensile properties and plasticity by polymerizing multiple monomers and copolymerizing rigid and semi-rigid anhydride groups and amino groups. The polymer material can be used for a long time at 200-260°C. When used as a vibration plate in an audio system, it can maintain high elasticity and high stiffness for a long time.

[0071] The polyimide vibration film prepared in Example 1 was subjected to a thermal decomposition test, and the obtained thermal decomposition curve is as follows: Figure 2 shown.

[0072] Depend on Figure 2 It can be seen that the film material prepared by introducing TFMB monomer in Example 1 has a thermal decomposition temperature reaching the requirement of above 500°C. It can maintain stable high-temperature resistance and high stiffness and excellent protection function in a high-temperature environment on the isolation tape of AI-TAB automatic welding, and can provide effective and temperature-resistant support and protection for the chip surface.

Claims

1. A production process for a polyimide vibration film, characterized in that: The following steps are involved: S1: 4,4'-diaminodiphenyl ether, 3,3,4,4-diphenyl ether tetracarboxylic dianhydride, 3,3,4,4,-biphenyl dianhydride and pyromellitic dianhydride are added as base materials into an organic solvent, stirred and dissolved, and the solid content is adjusted to 18-20wt.%, stirred and reacted at room temperature for 8-10h to obtain a prepolymer solution; the specific process of step S1 is as follows: 4,4'-diaminodiphenyl ether, 3,3,4,4-diphenyl ether tetracarboxylic dianhydride, 3,3,4,4,-biphenyl dianhydride and pyromellitic dianhydride are dissolved in an organic solvent respectively, and nitrogen is introduced for protection; the obtained 3,3,4,4,-biphenyl dianhydride solution is added into In the first reactor, after uniform stirring, the 4,4'-diaminodiphenyl ether solution and the 3,3,4,4-diphenyl ether tetracarboxylic dianhydride solution are gradually added. After stirring, the pyromellitic dianhydride solution is gradually added, and the mixture is uniformly stirred for 8-10 hours until the designed viscosity reaches 1, thereby obtaining a uniformly mixed prepolymer solution, which is then protected by nitrogen. In the base material, the molar ratio of 4,4'-diaminodiphenyl ether, 3,3,4,4-biphenyl dianhydride, 3,3,4,4-diphenyl ether tetracarboxylic dianhydride and pyromellitic dianhydride is 1:(0.3-0.39):(0.3-0.39):(0.3-0.34), and the molar ratio of anhydride to amine is 0.99:1; S2: adding 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl to an organic solvent and stirring to dissolve the solution to obtain a 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution, injecting the solution into a prepolymer solution to obtain a fluorinated polyamic acid solution having a solid content of 20-22 wt.%, degassing the solution and filtering the solution into a storage tank for temporary storage; the molar ratio of the solid in the fluorinated polyamic acid solution to the 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl is 1:(0.02-0.04); S3: adding acetic anhydride and isoquinoline to an organic solvent, mixing them evenly, defoaming them, and then filtering them into respective storage tanks for temporary storage; S4: The three materials in the storage tanks of step S2 and step S3 are transported to the pin-bar mixer above the die head, and after being fully mixed at -15~-5℃, they are coated onto an annular mirror steel belt through the slit extrusion die of a casting machine. The annular steel belt is dried in the casting machine to complete the preliminary imidization film shaping, and then the imidization is completed after shaping in a stretching machine, and finally rolled up to obtain a polyimide vibration film.

2. The production process of the polyimide vibration film according to claim 1, wherein: The design viscosity is 450,000-500,000 mPa·s at 25°C.

3. The production process of the polyimide vibration film according to claim 1, wherein: The specific process of step S2 is as follows: 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl is added to an organic solvent and stirred to dissolve to obtain a 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution, which is then protected by nitrogen; the 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl solution is injected into the prepolymer solution and adjusted to a designed viscosity of 2 to obtain a fluorinated polyamic acid solution, which is then protected by nitrogen; after degassing, the solution is filtered and temporarily stored in a storage tank.

4. The production process of the polyimide vibration film according to claim 3, wherein: The design viscosity is 1 million to 1.2 million mPa·s at 25°C.

5. The production process of the polyimide vibration film according to claim 1, wherein: In step S3, the mass of acetic anhydride is 30-35 times the mass of the base material, the mass ratio of acetic anhydride to the organic solvent is (0.8-1): (2.2-2.8), the mass of isoquinoline is 5.5-6.5 times the mass of the base material, and the mass ratio of isoquinoline to the organic solvent is (0.8-1): (3-5).

6. The production process of the polyimide vibration film according to claim 1, wherein: The upper drying temperature of the salivating machine is 135℃, and the lower drying temperature is 145℃; the setting temperature of the stretching machine is: 180-220℃ in the first zone hot air section, 200-240℃ in the second zone hot air section, 240-260℃ in the third zone infrared section, and 220-270℃ in the fourth zone infrared section.

7. A polyimide vibration film, characterized in that: The polyimide vibrating film is produced by the production process of the polyimide vibrating film according to any one of claims 1 to 6.

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